samples/tracepoints/tracepoint-probe-sample2.c

   1 /*
   2  * tracepoint-probe-sample2.c
   3  *
   4  * 2nd sample tracepoint probes.
   5  */
   6
   7 #include <linux/module.h>
   8 #include <linux/fs.h>
   9 #include "tp-samples-trace.h"
  10
  11 /*
  12  * Here the caller only guarantees locking for struct file and struct inode.
  13  * Locking must therefore be done in the probe to use the dentry.
  14  */
  15 static void probe_subsys_event(void *ignore,
  16                                struct inode *inode, struct file *file)
  17 {
  18         printk(KERN_INFO "Event is encountered with inode number %lu\n",
  19                 inode->i_ino);
  20 }
  21
  22 static int __init tp_sample_trace_init(void)
  23 {
  24         int ret;
  25
  26         ret = register_trace_subsys_event(probe_subsys_event, NULL);
  27         WARN_ON(ret);
  28
  29         return 0;
  30 }
  31
  32 module_init(tp_sample_trace_init);
  33
  34 static void __exit tp_sample_trace_exit(void)
  35 {
  36         unregister_trace_subsys_event(probe_subsys_event, NULL);
  37         tracepoint_synchronize_unregister();
  38 }
  39
  40 module_exit(tp_sample_trace_exit);
  41
  42 MODULE_LICENSE("GPL");
  43 MODULE_AUTHOR("Mathieu Desnoyers");
  44 MODULE_DESCRIPTION("Tracepoint Probes Samples");